Former New England Patriots player Aaron Hernandez, already facing charges in a murder last week in North Attleborough, is also being investigated in connection with a July 2012 double murder in Boston, according to two law enforcement officials briefed on the investigation.

Investigators believe a fight broke out at Cure, a club in the South End, between two men and a group that included Hernandez.

The two men, Daniel Abreu and Safiro Furtado, friends who grew up in Cape Verde, left the club with three other men in a BMW sedan in the early morning hours of July 16, 2012.

Abreu, who was driving, stopped at a traffic light on Shawmut Avenue, about to make a left onto Herald Street, when a silver or gray SUV with Rhode Island license plates pulled alongside the sedan. Someone from the SUV opened fire, killing Abreu, 29, and Furtado, 28.

The men who were with them survived the attack and the killings were left unsolved.

The officials said investigators now believe that Odin Lloyd, the man Hernandez is charged with killing in a North Attleborough industrial park June 17, may have had information about Hernandezís role in the double slaying.

ďThe motive might have been that the victim knew [Hernandez] might have been involved,Ē one of the officials said.

The new revelations raised the specter that Hernandez might have been playing football games last season with the Patriots after he had participated in a double murder.

Hernandez pleaded not guilty Wednesday to murder and firearms charges in Attleboro District Court in the killing of Lloyd, who was shot to death June 17 in an industrial park near Hernandezís North Attleborough home. In other news today, a second man connected to the Lloyd murder was identified: Carlos Ortiz, a 27-year-old man who lives in Bristol, Conn., Hernandezís hometown.

Police said the shooter in the July 2012 attack fired numerous times into the car, striking Abreu and Furtado, who was in the passenger seat.

One of the back-seat passengers was shot three times in the arm but survived. He was rushed to Tufts Medical Center and was treated and released. The other two occupants fled the car and were unharmed.

The two menís deaths at the time were a mystery to their families and police, who said they had no ties to criminal activity.

Furtado was a tour guide on the idyllic island of Boa Vista in Cape Verde, where he led a mostly European clientele on jaunts along silky sand dunes, whispering palm trees, and world-class beaches, his family said. He arrived in Dorchester five months before he was killed to reconnect with his mother and sister, whom he had not seen in a decade.

Abreu grew up in Cape Verde, where he worked as a police officer there. He arrived in Dorchester around 2008 and became friends with Furtado. The two men were working together for a cleaning company based on Hamilton Street in Dorchester at the time of their deaths.

Authorities never found the SUV tied to the shooting.

Hernandezís arraignment Wednesday in the killing of Lloyd came after a week of suspense in which media had camped out in front of Hernandezís home and followed his car by helicopter, in a futile search for details from tight-lipped law enforcement officials. Residents in Massachusetts and beyond have been riveted by the story of a young, highly paid professional athlete who may have squandered a bright future.